A Science Driven Life

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Archive for the ‘Science in Press’ Category

Quick Look: Another use for optogenetics and GPCR signaling

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Optogenetics is the rapidly emerging field in biotechnology and biological sciences that combines the genetic expression of light sensitive molecules and the delivery of light to control cells, populations of cells or animal behavior.  Often when we think of optogenetics, the first thought is back to the landmark papers where light was used to depolarize cells and cause action potentials (Zemelman et al. 2002, Boyden et al. 2005).  While these types of studies are highly prevalent in neuroscience today, a whole other branch of optogenetics exists that uses light sensitive molecules to modulate some biochemical or second messanger pathway.  One area, called OptoXRs, is of great interest as therapeautic targets for a variety of pharmaceutical products as a majority of these act through some type of g-protein coupled receptor (GPCR) pathway.


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Written by Michael Mohammadi

September 9, 2013 at 19:56

Science in press: A look at two recent papers- Optogenetics to control GPCRs and optogenetics in monkeys!

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English: Based on PDB 1hzx and the Heller/Schaefer/Schulten lipid bilayer coordinates.

English: Based on PDB 1hzx and the Heller/Schaefer/Schulten lipid bilayer coordinates.

by Michael Mohammadi

Being free from the “chains” of academia I have been able to expand my scientific interests well beyond NMDA receptor signaling and short term memory.  I do miss actually producing research from time to time, but I now average 6 papers read in a week which is about double (or more) what I read in grad school so I’m still feel like I’m part of the process.  I do have the luxury of spending a lot of time in planes and on trains, both excellent venues for diving into a paper with few distractions (Bose noise canceling headphones are essential!).  I have found that it is liberating to be able to read articles from all different fields of science and not be limited to a very specific field or research question.  Exploring new research in neuroscience, physiology, physics, optics, imaging and more has really rejuvenated my spirit for science and discovery, a spirit that had faded over the long duration of wrapping up my dissertation.  Now that this curiosity and excitement is back and fully charged, I hope to share some of the cool papers I’m reading with you.  It is my goal with this “Science in press” series that I review a few papers that I have read in the last few weeks that really stood out.  These may be a bit more technical than my other articles, but I hope to keep it accessible to the mainstream reader.  As always, questions are encouraged.

For this first installment I tried to cover 5 papers I read recently, but I ended up a bit too excited and went into a lot of detail on paper one.  I’ll try to be more concise in the future if it’s more interesting to get into the details let me know, I would enjoy writing either way!  So I ended up giving overviews of two recent papers in Nature Neuroscience.

I welcome criticisms and feedback, suggestions on papers to read, as well as corrections to my interpretations or explanations of the experimental design, results or conclusions.  I accept I may get things wrong and hope to learn from my readers.  Without further ado…

1.  Optical control of metabotropic glutamate receptors. Levitz et al, 2013 Nature Neuroscience

I’ll start with a recent paper that employs optogenetics for something other than direct gating of ion channels!  Dr. Ehud Isacoff’s group at UC Berkely has been doing some amazing work in the field of molecular engineering with optical probes (among other things).  Previous work included a very cool probe called HyLighter (of which some data was acquired with the Mosaic) that is a light-activated glutamate channel that selectively gates K+.  In this most recent paper, Levitz et al describe a metabotropic glutamate receptor (mGluR) which is a specific type of G-Protein Coupled Receptor (GPCR; the most abundant receptor type in the body) that they have engineered to respond to specific wavelengths of light which results in a variety of downstream G-protein regulated outputs. Read the rest of this entry »